blob: 144e448a04d4a77fbd4d52fd05e47e0bd86c460a [file] [log] [blame]
/*
* Copyright (c) 2017 Jean-Paul Etienne <fractalclone@gmail.com>
* Copyright (c) 2023 Meta
* Contributors: 2018 Antmicro <www.antmicro.com>
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT sifive_plic_1_0_0
/**
* @brief Platform Level Interrupt Controller (PLIC) driver
* for RISC-V processors
*/
#include <stdlib.h>
#include "sw_isr_common.h"
#include <zephyr/kernel.h>
#include <zephyr/arch/cpu.h>
#include <zephyr/device.h>
#include <zephyr/devicetree/interrupt_controller.h>
#include <zephyr/shell/shell.h>
#include <zephyr/sw_isr_table.h>
#include <zephyr/drivers/interrupt_controller/riscv_plic.h>
#include <zephyr/irq.h>
#define PLIC_BASE_ADDR(n) DT_INST_REG_ADDR(n)
/*
* These registers' offset are defined in the RISCV PLIC specs, see:
* https://github.com/riscv/riscv-plic-spec
*/
#define CONTEXT_BASE 0x200000
#define CONTEXT_SIZE 0x1000
#define CONTEXT_THRESHOLD 0x00
#define CONTEXT_CLAIM 0x04
#define CONTEXT_ENABLE_BASE 0x2000
#define CONTEXT_ENABLE_SIZE 0x80
/*
* Trigger type is mentioned, but not defined in the RISCV PLIC specs.
* However, it is defined and supported by at least the Andes & Telink datasheet, and supported
* in Linux's SiFive PLIC driver
*/
#define PLIC_TRIG_LEVEL ((uint32_t)0)
#define PLIC_TRIG_EDGE ((uint32_t)1)
#define PLIC_DRV_HAS_COMPAT(compat) \
DT_NODE_HAS_COMPAT(DT_COMPAT_GET_ANY_STATUS_OKAY(DT_DRV_COMPAT), compat)
#if PLIC_DRV_HAS_COMPAT(andestech_nceplic100)
#define PLIC_SUPPORTS_TRIG_TYPE 1
#define PLIC_REG_TRIG_TYPE_WIDTH 1
#define PLIC_REG_TRIG_TYPE_OFFSET 0x1080
#else
/* Trigger-type not supported */
#define PLIC_REG_TRIG_TYPE_WIDTH 0
#endif
/* PLIC registers are 32-bit memory-mapped */
#define PLIC_REG_SIZE 32
#define PLIC_REG_MASK BIT_MASK(LOG2(PLIC_REG_SIZE))
#ifdef CONFIG_TEST_INTC_PLIC
#define INTC_PLIC_STATIC
#else
#define INTC_PLIC_STATIC static inline
#endif
typedef void (*riscv_plic_irq_config_func_t)(void);
struct plic_config {
mem_addr_t prio;
mem_addr_t irq_en;
mem_addr_t reg;
mem_addr_t trig;
uint32_t max_prio;
uint32_t num_irqs;
riscv_plic_irq_config_func_t irq_config_func;
struct _isr_table_entry *isr_table;
};
struct plic_stats {
uint16_t *const irq_count;
const int irq_count_len;
};
struct plic_data {
struct plic_stats stats;
};
static uint32_t save_irq;
static const struct device *save_dev;
INTC_PLIC_STATIC uint32_t local_irq_to_reg_index(uint32_t local_irq)
{
return local_irq >> LOG2(PLIC_REG_SIZE);
}
INTC_PLIC_STATIC uint32_t local_irq_to_reg_offset(uint32_t local_irq)
{
return local_irq_to_reg_index(local_irq) * sizeof(uint32_t);
}
static inline uint32_t get_plic_enabled_size(const struct device *dev)
{
const struct plic_config *config = dev->config;
return local_irq_to_reg_index(config->num_irqs) + 1;
}
static inline uint32_t get_first_context(uint32_t hartid)
{
return hartid == 0 ? 0 : (hartid * 2) - 1;
}
static inline mem_addr_t get_context_en_addr(const struct device *dev, uint32_t cpu_num)
{
const struct plic_config *config = dev->config;
uint32_t hartid;
/*
* We want to return the irq_en address for the context of given hart.
* If hartid is 0, we return the devices irq_en property, job done. If it is
* greater than zero, we assume that there are two context's associated with
* each hart: M mode enable, followed by S mode enable. We return the M mode
* enable address.
*/
#if CONFIG_SMP
hartid = _kernel.cpus[cpu_num].arch.hartid;
#else
hartid = arch_proc_id();
#endif
return config->irq_en + get_first_context(hartid) * CONTEXT_ENABLE_SIZE;
}
static inline mem_addr_t get_claim_complete_addr(const struct device *dev)
{
const struct plic_config *config = dev->config;
/*
* We want to return the claim complete addr for the hart's context.
* We are making a few assumptions here:
* 1. for hart 0, return the first context claim complete.
* 2. for any other hart, we assume they have two privileged mode contexts
* which are contiguous, where the m mode context is first.
* We return the m mode context.
*/
return config->reg + get_first_context(arch_proc_id()) * CONTEXT_SIZE +
CONTEXT_CLAIM;
}
static inline mem_addr_t get_threshold_priority_addr(const struct device *dev, uint32_t cpu_num)
{
const struct plic_config *config = dev->config;
uint32_t hartid;
#if CONFIG_SMP
hartid = _kernel.cpus[cpu_num].arch.hartid;
#else
hartid = arch_proc_id();
#endif
return config->reg + (get_first_context(hartid) * CONTEXT_SIZE);
}
/**
* @brief Determine the PLIC device from the IRQ
*
* @param irq IRQ number
*
* @return PLIC device of that IRQ
*/
static inline const struct device *get_plic_dev_from_irq(uint32_t irq)
{
#ifdef CONFIG_DYNAMIC_INTERRUPTS
return z_get_sw_isr_device_from_irq(irq);
#else
return DEVICE_DT_INST_GET(0);
#endif
}
/**
* @brief Return the value of the trigger type register for the IRQ
*
* In the event edge irq is enable this will return the trigger
* value of the irq. In the event edge irq is not supported this
* routine will return 0
*
* @param dev PLIC-instance device
* @param local_irq PLIC-instance IRQ number to add to the trigger
*
* @return Trigger type register value if PLIC supports trigger type, PLIC_TRIG_LEVEL otherwise
*/
static uint32_t __maybe_unused riscv_plic_irq_trig_val(const struct device *dev, uint32_t local_irq)
{
if (!IS_ENABLED(PLIC_SUPPORTS_TRIG_TYPE)) {
return PLIC_TRIG_LEVEL;
}
const struct plic_config *config = dev->config;
mem_addr_t trig_addr = config->trig + local_irq_to_reg_offset(local_irq);
uint32_t offset = local_irq * PLIC_REG_TRIG_TYPE_WIDTH;
return sys_read32(trig_addr) & GENMASK(offset + PLIC_REG_TRIG_TYPE_WIDTH - 1, offset);
}
static void plic_irq_enable_set_state(uint32_t irq, bool enable)
{
const struct device *dev = get_plic_dev_from_irq(irq);
const uint32_t local_irq = irq_from_level_2(irq);
for (uint32_t cpu_num = 0; cpu_num < arch_num_cpus(); cpu_num++) {
mem_addr_t en_addr =
get_context_en_addr(dev, cpu_num) + local_irq_to_reg_offset(local_irq);
uint32_t en_value;
uint32_t key;
key = irq_lock();
en_value = sys_read32(en_addr);
WRITE_BIT(en_value, local_irq & PLIC_REG_MASK, enable);
sys_write32(en_value, en_addr);
irq_unlock(key);
}
}
/**
* @brief Enable a riscv PLIC-specific interrupt line
*
* This routine enables a RISCV PLIC-specific interrupt line.
* riscv_plic_irq_enable is called by RISCV_PRIVILEGED
* arch_irq_enable function to enable external interrupts for
* IRQS level == 2, whenever CONFIG_RISCV_HAS_PLIC variable is set.
*
* @param irq IRQ number to enable
*/
void riscv_plic_irq_enable(uint32_t irq)
{
plic_irq_enable_set_state(irq, true);
}
/**
* @brief Disable a riscv PLIC-specific interrupt line
*
* This routine disables a RISCV PLIC-specific interrupt line.
* riscv_plic_irq_disable is called by RISCV_PRIVILEGED
* arch_irq_disable function to disable external interrupts, for
* IRQS level == 2, whenever CONFIG_RISCV_HAS_PLIC variable is set.
*
* @param irq IRQ number to disable
*/
void riscv_plic_irq_disable(uint32_t irq)
{
plic_irq_enable_set_state(irq, false);
}
/**
* @brief Check if a riscv PLIC-specific interrupt line is enabled
*
* This routine checks if a RISCV PLIC-specific interrupt line is enabled.
* @param irq IRQ number to check
*
* @return 1 or 0
*/
int riscv_plic_irq_is_enabled(uint32_t irq)
{
const struct device *dev = get_plic_dev_from_irq(irq);
const struct plic_config *config = dev->config;
const uint32_t local_irq = irq_from_level_2(irq);
mem_addr_t en_addr = config->irq_en + local_irq_to_reg_offset(local_irq);
uint32_t en_value;
en_value = sys_read32(en_addr);
en_value &= BIT(local_irq & PLIC_REG_MASK);
return !!en_value;
}
/**
* @brief Set priority of a riscv PLIC-specific interrupt line
*
* This routine set the priority of a RISCV PLIC-specific interrupt line.
* riscv_plic_irq_set_prio is called by riscv arch_irq_priority_set to set
* the priority of an interrupt whenever CONFIG_RISCV_HAS_PLIC variable is set.
*
* @param irq IRQ number for which to set priority
* @param priority Priority of IRQ to set to
*/
void riscv_plic_set_priority(uint32_t irq, uint32_t priority)
{
const struct device *dev = get_plic_dev_from_irq(irq);
const struct plic_config *config = dev->config;
const uint32_t local_irq = irq_from_level_2(irq);
mem_addr_t prio_addr = config->prio + (local_irq * sizeof(uint32_t));
if (priority > config->max_prio)
priority = config->max_prio;
sys_write32(priority, prio_addr);
}
/**
* @brief Get riscv PLIC-specific interrupt line causing an interrupt
*
* This routine returns the RISCV PLIC-specific interrupt line causing an
* interrupt.
*
* @param dev Optional device pointer to get the interrupt line's controller
*
* @return PLIC-specific interrupt line causing an interrupt.
*/
unsigned int riscv_plic_get_irq(void)
{
return save_irq;
}
const struct device *riscv_plic_get_dev(void)
{
return save_dev;
}
static void plic_irq_handler(const struct device *dev)
{
const struct plic_config *config = dev->config;
mem_addr_t claim_complete_addr = get_claim_complete_addr(dev);
struct _isr_table_entry *ite;
uint32_t __maybe_unused trig_val;
/* Get the IRQ number generating the interrupt */
const uint32_t local_irq = sys_read32(claim_complete_addr);
#ifdef CONFIG_PLIC_SHELL
const struct plic_data *data = dev->data;
struct plic_stats stat = data->stats;
/* Cap the count at __UINT16_MAX__ */
if (stat.irq_count[local_irq] != __UINT16_MAX__) {
stat.irq_count[local_irq]++;
}
#endif /* CONFIG_PLIC_SHELL */
/*
* Save IRQ in save_irq. To be used, if need be, by
* subsequent handlers registered in the _sw_isr_table table,
* as IRQ number held by the claim_complete register is
* cleared upon read.
*/
save_irq = local_irq;
save_dev = dev;
/*
* If the IRQ is out of range, call z_irq_spurious.
* A call to z_irq_spurious will not return.
*/
if (local_irq == 0U || local_irq >= config->num_irqs) {
z_irq_spurious(NULL);
}
#if IS_ENABLED(PLIC_DRV_HAS_COMPAT(andestech_nceplic100))
trig_val = riscv_plic_irq_trig_val(dev, local_irq);
/*
* Edge-triggered interrupts on Andes NCEPLIC100 have to be acknowledged first before
* getting handled so that we don't miss on the next edge-triggered interrupt.
*/
if (trig_val == PLIC_TRIG_EDGE) {
sys_write32(local_irq, claim_complete_addr);
}
#endif
/* Call the corresponding IRQ handler in _sw_isr_table */
ite = &config->isr_table[local_irq];
ite->isr(ite->arg);
/*
* Write to claim_complete register to indicate to
* PLIC controller that the IRQ has been handled
* for level triggered interrupts.
*/
#if IS_ENABLED(PLIC_DRV_HAS_COMPAT(andestech_nceplic100))
/* For NCEPLIC100, handle only if level-triggered */
if (trig_val == PLIC_TRIG_LEVEL) {
sys_write32(local_irq, claim_complete_addr);
}
#else
sys_write32(local_irq, claim_complete_addr);
#endif
}
/**
* @brief Initialize the Platform Level Interrupt Controller
*
* @param dev PLIC device struct
*
* @retval 0 on success.
*/
static int plic_init(const struct device *dev)
{
const struct plic_config *config = dev->config;
mem_addr_t en_addr, thres_prio_addr;
mem_addr_t prio_addr = config->prio;
/* Iterate through each of the contexts, HART + PRIV */
for (uint32_t cpu_num = 0; cpu_num < arch_num_cpus(); cpu_num++) {
en_addr = get_context_en_addr(dev, cpu_num);
thres_prio_addr = get_threshold_priority_addr(dev, cpu_num);
/* Ensure that all interrupts are disabled initially */
for (uint32_t i = 0; i < get_plic_enabled_size(dev); i++) {
sys_write32(0U, en_addr + (i * sizeof(uint32_t)));
}
/* Set threshold priority to 0 */
sys_write32(0U, thres_prio_addr);
}
/* Set priority of each interrupt line to 0 initially */
for (uint32_t i = 0; i < config->num_irqs; i++) {
sys_write32(0U, prio_addr + (i * sizeof(uint32_t)));
}
/* Configure IRQ for PLIC driver */
config->irq_config_func();
return 0;
}
#ifdef CONFIG_PLIC_SHELL
static inline int parse_device(const struct shell *sh, size_t argc, char *argv[],
const struct device **plic)
{
ARG_UNUSED(argc);
*plic = device_get_binding(argv[1]);
if (*plic == NULL) {
shell_error(sh, "PLIC device (%s) not found!\n", argv[1]);
return -ENODEV;
}
return 0;
}
static int cmd_get_stats(const struct shell *sh, size_t argc, char *argv[])
{
const struct device *dev;
int ret = parse_device(sh, argc, argv, &dev);
uint16_t min_hit = 0;
if (ret != 0) {
return ret;
}
const struct plic_data *data = dev->data;
struct plic_stats stat = data->stats;
if (argc > 2) {
min_hit = (uint16_t)atoi(argv[2]);
shell_print(sh, "IRQ line with > %d hits:", min_hit);
}
shell_print(sh, " IRQ\t Hits");
shell_print(sh, "==================");
for (int i = 0; i < stat.irq_count_len; i++) {
if (stat.irq_count[i] > min_hit) {
shell_print(sh, "%6d\t%10d", i, stat.irq_count[i]);
}
}
shell_print(sh, "");
return 0;
}
static int cmd_clear_stats(const struct shell *sh, size_t argc, char *argv[])
{
const struct device *dev;
int ret = parse_device(sh, argc, argv, &dev);
if (ret != 0) {
return ret;
}
const struct plic_data *data = dev->data;
struct plic_stats stat = data->stats;
memset(stat.irq_count, 0, stat.irq_count_len * sizeof(uint16_t));
shell_print(sh, "Cleared stats of %s.\n", dev->name);
return 0;
}
/* Device name autocompletion support */
static void device_name_get(size_t idx, struct shell_static_entry *entry)
{
const struct device *dev = shell_device_lookup(idx, NULL);
entry->syntax = (dev != NULL) ? dev->name : NULL;
entry->handler = NULL;
entry->help = NULL;
entry->subcmd = NULL;
}
SHELL_DYNAMIC_CMD_CREATE(dsub_device_name, device_name_get);
SHELL_STATIC_SUBCMD_SET_CREATE(plic_stats_cmds,
SHELL_CMD_ARG(get, &dsub_device_name,
"Read PLIC's stats.\n"
"Usage: plic stats get <device> [minimum hits]",
cmd_get_stats, 2, 1),
SHELL_CMD_ARG(clear, &dsub_device_name,
"Reset PLIC's stats.\n"
"Usage: plic stats clear <device>",
cmd_clear_stats, 2, 0),
SHELL_SUBCMD_SET_END
);
SHELL_STATIC_SUBCMD_SET_CREATE(plic_cmds,
SHELL_CMD_ARG(stats, &plic_stats_cmds, "PLIC stats", NULL, 3, 0),
SHELL_SUBCMD_SET_END
);
static int cmd_plic(const struct shell *sh, size_t argc, char **argv)
{
shell_error(sh, "%s:unknown parameter: %s", argv[0], argv[1]);
return -EINVAL;
}
SHELL_CMD_ARG_REGISTER(plic, &plic_cmds, "PLIC shell commands",
cmd_plic, 2, 0);
#define PLIC_MIN_IRQ_NUM(n) MIN(DT_INST_PROP(n, riscv_ndev), CONFIG_MAX_IRQ_PER_AGGREGATOR)
#define PLIC_INTC_IRQ_COUNT_BUF_DEFINE(n) \
static uint16_t local_irq_count_##n[PLIC_MIN_IRQ_NUM(n)];
#define PLIC_INTC_DATA_INIT(n) \
PLIC_INTC_IRQ_COUNT_BUF_DEFINE(n); \
static struct plic_data plic_data_##n = { \
.stats = { \
.irq_count = local_irq_count_##n, \
.irq_count_len = PLIC_MIN_IRQ_NUM(n), \
}, \
};
#define PLIC_INTC_DATA(n) &plic_data_##n
#else
#define PLIC_INTC_DATA_INIT(...)
#define PLIC_INTC_DATA(n) (NULL)
#endif
#define PLIC_INTC_IRQ_FUNC_DECLARE(n) static void plic_irq_config_func_##n(void)
#define PLIC_INTC_IRQ_FUNC_DEFINE(n) \
static void plic_irq_config_func_##n(void) \
{ \
IRQ_CONNECT(DT_INST_IRQN(n), 0, plic_irq_handler, DEVICE_DT_INST_GET(n), 0); \
irq_enable(DT_INST_IRQN(n)); \
}
#define PLIC_INTC_CONFIG_INIT(n) \
PLIC_INTC_IRQ_FUNC_DECLARE(n); \
static const struct plic_config plic_config_##n = { \
.prio = PLIC_BASE_ADDR(n), \
.irq_en = PLIC_BASE_ADDR(n) + CONTEXT_ENABLE_BASE, \
.reg = PLIC_BASE_ADDR(n) + CONTEXT_BASE, \
IF_ENABLED(PLIC_SUPPORTS_TRIG_TYPE, \
(.trig = PLIC_BASE_ADDR(n) + PLIC_REG_TRIG_TYPE_OFFSET,)) \
.max_prio = DT_INST_PROP(n, riscv_max_priority), \
.num_irqs = DT_INST_PROP(n, riscv_ndev), \
.irq_config_func = plic_irq_config_func_##n, \
.isr_table = &_sw_isr_table[INTC_INST_ISR_TBL_OFFSET(n)], \
}; \
PLIC_INTC_IRQ_FUNC_DEFINE(n)
#define PLIC_INTC_DEVICE_INIT(n) \
IRQ_PARENT_ENTRY_DEFINE( \
plic##n, DEVICE_DT_INST_GET(n), DT_INST_IRQN(n), \
INTC_INST_ISR_TBL_OFFSET(n), \
DT_INST_INTC_GET_AGGREGATOR_LEVEL(n)); \
PLIC_INTC_CONFIG_INIT(n) \
PLIC_INTC_DATA_INIT(n) \
DEVICE_DT_INST_DEFINE(n, &plic_init, NULL, \
PLIC_INTC_DATA(n), &plic_config_##n, \
PRE_KERNEL_1, CONFIG_INTC_INIT_PRIORITY, \
NULL);
DT_INST_FOREACH_STATUS_OKAY(PLIC_INTC_DEVICE_INIT)